Abstract

Background : Shivering is the most common side effect of' spinal anesthesia which has to be prevented by using fluid and / or vasopressors. I.m. ephedrine has been established to prevent shivering, but it has some adverse effects to cardiocirculation due to unstable absorpstion. Oral ephedrine is an alternative agent for preventing shivering with less adverse effects to cardiocirculation.
Methods : Second phase of third level clinical randomized controlled test. Forty six patients electively programmed for lower abdominal, perineum, and lower extremities surgery were divided into I.M.. ephedrine (23 patients) and Oral ephedrine (23 patients) group. I.M group was injected with i.m. 0,6 mg/kgBW immediately after spinal anesthesia performed, and oral group was given encapsulated ephedrine 0,6 mg/kgBB and ± 20 ml plain water 60 minutes before performing spinal anesthesia. Blood pressure (systolic, diastolic, and mean arterial pressure / MAP), heart rate, and respiratory rate were measured immediately after spinal anesthesia and serially repeated every 2 minutes. Data was analyzed using student t-test and chi-square at significancy level of 0,05
Results : Both groups have similar distribution on sex, age, body weight, early clinical state, level of block anesthesia. No patient developed shivering in I.M Group whereas a patient of Oral group developed shivering, but there is no significant different. Sistolic blood pressure decreased -6,13 + 11,79 mmHg in Oral group and -7,70 ± 19,43 mmHg in I.M group (p = 0,74). The incidence of hypotension between the two groups is not significantly different. Incidence of hypertension between the two groups is significantly different (I.M group 9 patients, Oral Group 1 patients). Systolic blood pressure increased 23,61 ± 18,97 mmHg in IM Group and 13,74 ± 6,99 mmHg in Oral Group (p=0,02). The incidence of tachycardia, there is no significant different on both group, but the increase of heart rate is significantly different (p = 0,02). No significant difference in the increase of respiratory rate in both group.
Conclusion : Oral ephedrine 0,6 mg/kgBW is as effective as ephedrine 0,6 mg/kgBW i.m for preventing shivering in spinal anesthesia and have less adverse effect on blood pressure and heart rate compared with ephedrine 0,6 mg/kgBW i.m.
Keywords : Oral ephedrine, i.m. ephedrine, shivering, spinal anesthesia